Hot melt adhesives produce a bond by cooling of the adhesive, which is applied in a melted state. Hot melt adhesives are distinguishable from those products which require crosslinking or other chemical reactions to achieve ultimate bond strength or from those materials that require loss of solvent or water to achieve bond strength. Prior to heating, the hot melt adhesives are solids that can be provided in bulk or in pelletized or rod form for ease of handling. Upon heating, the hot melt adhesive composition melts rather sharply and flows readily for application to a substrate. Since the hot melt adhesives are thermoplastic rather than thermosetting, and are thus remeltable, they can be applied to a first substrate and later remelted to form a hot melt bond with a second substrate.
While many satisfactory hot melt adhesives are available to the art, the art is constantly seeking new compositions having superior performance or lower cost or both.
There are a variety of uses for hot melt adhesives. However, it has been found that while one hot melt adhesive may be used for bonding in a particular use or application, the adhesive may be completely unsuitable for other uses or applications.